Combined type-writing and computing machine.



w. wmGHT`. COMBINED TYPE WRITING AND COMPUTING MACHINE. APPLICATIONFILED DEC. l. 19H.

RENEWED IULY 1I. |912.

W. WRIGHT. COMBINED TYPE WRTING AND COMPUTING MACHlNE.

APPLlcAloN min nic. x. 19:1.

RENEWED JULY l l| |912 Patented Nov. 6, 1917.

a INVENTOR 'Maw/W' gy .V

e .om

WITNESS ESz' ATTORNE( "UNITED STATES' 'lnrENT OFFICE.

Sldcicaitionof Letters Patent.

Patenwdnwe, 19m.

ToaZZAw/wm it may 'ciboeifizl'f l l,

, Bc it 4known tht fl, IJER'IWMGHT, n Citizen of theUniced'seifesgres'idii magen York city, in theY coliii'ty 'of vAY, 'okn' Stute of New York, have inventedlceftn new :ind use'fiillir-np'rrveniefitsfjCinb'iied 'lype-lYriting and Compii'tinflgrMchiiegof which lthe following is a specification.

This invention relzite's toe-'new proved key controlledcorrectioniec'iieniin to be used in connection 'with a combined ty pewriting and vcomputing 'Inachine 'of 'the Underwood-Wright type,' ind,$improve'- inent on, applications No. 54:5;603, "filed Fehruiiry" 1 2,1,5210 alfdwN'o.A 660,392, filed Noveinberfl5, l1911. l i f f In `1nyabove-,mentioned application No. 660,392, I have pmvided'means'whefbyxife state of a computing head Cain, be-chiid ltojust 'theopposite state A Wiltlhiti iritefllig'g iwith the directState,contrllnghiecliiexn of thecompiitinghead, by inteposingfbe- 4tWeen lthe source `of Epoiie'r"A and 'the contr-'o :ing more nearly'connected to thefconipiting head, -and having the individiialfstteControlling lnechzinisin interposed between it and the computing head. flhi's`,'whil e useful with a single4 ,computing 'head'its .O'a specialadvantage Where; n .plurality f coinvmusly committed 4cen 'loe` theactive computing heads, fwheth'er sci ne had been adding, Sonie`neut'rl, Some Silbkeys which struck the erroneois'uniefa AS'in the firstplace. l

In the :UnderWoodWright 'typey-'offtype- Writing: and computingrnaohi'esh after "the striking of a character, Y. the 'typewriterf''zirletter spce of the Work"sheetoppositeto "the printing point.A Thenioyenent of the travelingelements of the e'm'ptinglhexid's, whichinithisinsita-nce are .shown to bethenaster wheels is controlledyconcomitant-,ly with the movement ofthe carriaqfe, So is to ac'tilatethenext computing or'dial Wheel utgthenext stroke of a 'numeraikey LItis therefore neceesary in'orrecting-an error tohlng the carriage "becktofthe l'etter :spac'ef'ctr Cli'n'h in `which theiexror we'coriimttedfsbes fo brin -theniaeter inco ceperw tion'with 'he propercoinputi'igvviheels,'and iil'soso as tostrke-thennmeml ext-the sainepoint on theWo'fksheet. As the operator generallynbtice's theerrorfimmediately, the cafrriafge and traveling lements :may be broughtback by'efbk-fspcr "key 'This :ke-'y may be aise used-e0 ehenge-'eh'estatue elf Lthe ctive cdrnputingheeds.

An ohjedt'tli'eiefre of this invention is to control "coricxnititlytliei'etun -of Ithe jcal-rriage midline crawling 'elements -of the' com-'putingfheads ma previmfs=-1etti-spa eine n :hn'ge in' 'state "of ill:the lactive computing heads to just-theopposi'te'st1te, xherbyn 'error'committed in 's'id 'letter space 'can eliminated from allbf lie'computing heds containing it.

To :accomplish this" dbfvj ect, the-"back" spacer key is connected so asto :not only Shift th'e carriage brick to one orm'ote Eletter spa'c'es,Abut 'aise te feniporaly hift the lrev@rising innechmiiein between thesource-oil? dpower :xnd the gearing "for all the 'compitil'i'g hed's,ydrive the active elements 'df theebmputing 'heads in j 1 1's`ttheop'posi'te direction, whereby such `o' said -c'om'pti'ng heads aswere sdbtracting, t this Vpztrtic-ula'r letter space xW`ill` add, 'ndVice versa. Y therfeatu'resend-adventages-wllherenfferiarpn 1 Referringtotlie drawings,

igre 1 i`s l aVJ side vieWinelevation-With partei-in section.

Fig.' 2' is 'n diagrammatic perspective View encmit'ntly beck A'epilees.theeri-afge 'and shifts" the reversing meehnism locte'd 2on 'thedrivebtween the metor'andfthe gearing connected It'o the 'computinghea'ds.

les

- cured; res ectively the means for shifting one of the clutches of the;reversing mechanism.

Fig.f7is a detail of the tens carrying driving ear, and

Fig. 8 1s a detail 'perspective view showing the back spacing mechanismin the act of shiftingthe carriage.

Referring more particularly to the separate parts of this inventionas'em-bodied in" the form shown in the drawings, 1 indicates letter keys,and 2'numeral keys,'which are securedv to key levers `3, which operatethrough the intermediary' of bell cranks'4, typebars 5, so las .to swingthe latter up against the front sidevlofa platen 6 carried by a carriage7, whichslides on one or more rails 8. The letter-feeding movement ofthe carriage 7 may Ibeobtained in the usual man ner step-.byfstepatjeach actuation ofakey by the release of an escapementmechanism,indicated generally bythe numeral 9, which nav be of the usual Underwoodtype, and is described more particularly hereinafter.

..Thexcomputing mechanism may be controlled from lthe'n ume'rz'rl keysin the manvner described in my application No. 543,603, .wherein jit wasshown that each numeral key'leve'r 3 wasadapte'd to pulldown on a link10, so as to rock a bell crank 11, thereby pulling on a link 12 to swinga lever 13 about its.pivot, 14. The :swinging .of each, ofthe.'leversl3, of whichthereislone for each numeral key,.plunges a jack 15againsta cor- .responding 1pinl provided in a masteror fvaluating w isnormally v `the.projected p ins 16 engagin eel 17. The valuating wheel17 held from rotation by one of an escapementwheell 18, lwhich is secure.toanother escapement wheel 19 engaging one of a pair of locking stops2O on a rock shaft 21.

The rock shaft l21 is oscillated at each actuation of a .numeral key, soas to release the escapement wheels 18 and l19, and thus permit arotation jof the master or valuating wheel 17 alpredetermined amount,depending upon the particular numeral key actuated,.until the nextprojected in 16 engages the1escapement wheel 18. e rocking of the shaft21 may be accomplished .by a collar A.150- beingpushed backby each ofthe levers l 13 at the. actuation of a numeral key against the tensionof a spring 151, so as to, oscillate a lever 152 which is connectedby-.alink 153 to an arm 154 on the shaft v21.

- .This mechanism, which maf;r` be 'termed the escapement or valuatingmechanism for ithe. computing mechanism, determines the extent ofrotation of a shaft22, to which the valuating wheel 17 is secured, andwhich is provided, with a gear 23 meshing with a correspondingl gear 23on a shaft 24. The

shaft 24 is also provided with a bevel gear bevel gears 26 and 27 setoshafts 28and 29. The shaft 29 1s driven from a motor 30 through 25meshing with the intermediary of a slip clutch not shown, and alsothrough the intermediary of intermeshing bevel gears 31 and 32, thelatter of which is secured to the shaft 29. The shafts 28 and 29 form aportion-of the gearing connecting the motor 30 with the gearing fordriving the rotatable parts of one or more computing heads 33 and 34, ofwhich two areshown.

Each of the computing heads is preferably of the type shownin myapplication No. 543,603 above-mentioned, and includes, as will be seenby reference to Fig. 3, a master wheel 35 splinedon a shaft 36, so as tohave a movement relative to a series of computing wheels 37, whereby itwill be capable of enaging with the internal gears 38 provided y theinwardly projecting teeth of these vcomputing wheels, thus enabling themaster wheel to successively actuate each of these computing wheels. Therelative movement of the .master wheel4 and the computing wheels maybeobtained in any suitable manner, 'as for example that described in my'eo-'pending application No. 574,813, filed August 1, 1910, wherein themaster wheels are manipulated stepbystep at each. new column by a lever105 provided with an automatic catch 100, which is engaged and operatedby Aa series of column stops 101 lcarried vby a rack 102 on t-hecarriage4 These'co'mputing wheels are also provided with external teethforming external gears 39 lmeshing with the'gears 40 carrying thedialwheels 41, so that the numerals marked on therdial'wheels will beexhibited through an opening 42 in the casing of each computing head,thereby showing the particular computation run u by the numeral keys.Each of the shafts 36 for the computing heads 33 and 34 is provided witha bevel gear, indicated for the respective computing v eadsby'thenumerals 43 and 44. These bevel 4'gears each mesh with a pair of 'bevelears 'oosely mounted on a shaft 45 and aced. in opposite directions, soas to be capable of rotating the gears 43 and 44 in opposite directions,according to which member of the pair is rotated. To connect the pairsof bevel gears, which are indicated by the numerals 46, 47 ,'48 and 49,in driving relation with the shaft 45, there are provided clutches 50and 51 splined on the v shaft .45, so as to be shiftable to cause theteeth provided on opposite/ends thereof to engage with correspondingteeth on the iny wardly facing sides of each member of the pairs ofbevel gears. 4 j

-Each of the clutches is provided with a circular groove, so as 'to beengaged by pins 52 carried by shifting levers 53 and 54. The shiftinglevers 53 and 54 are pivoted respectively at 55 and 56 by means of pins,and are capable of occupving any one of three positions corresponding tothe con- .gagement with the pinion 110.

the carriage 7 to bring the carriage back to a previous letter space forthe purpose of correcting an error is accomplished in this instance bythe depression of a key 113 secured to a key lever 114 secured to a rockshaft 115.

Secured to the shaft 115 there is provided an arm 115 which hasextending upwardly therefrom a link bar 116, which is pivotallyconnected to an arm 117 extending to one side of and secured to anactuating pawl 118. The pawl 118 is also indirectly connected to thelink bar 116 by having an arm 119 extending in the opposite directionfrom the arm 117 and connected to a pin 120 on the link bar 116 by meansof a spring 121. This arrangement permits the bodily movement of thepaivl 118 before rocking on its pivot 122, because of the fact thatthere is a substantially equal pull on each side of the pivot 122 of thepawl.

The pivot 122 of the pawl 118 is mounted on a rocker 123, Which ispivoted at 124 so as to permit the rocker 123 to swing toward the rack111 and bring thel point of the paWl 118 into engagement with the teethof the rack 111. The rocker 123 is provided .with an overhang 125, whichWill overlie the rack 111 in its engaging position and prevent thedisengagement of the rack from the pinion 11OWhile the .p'aWl 118 is inengagement therewith.` The rocker 123, however, is normally held out ofengagement with the rack 111, and thus also the pawl 118 is normallyheld out 0f engagement with the rack-111 by means-of a spring-pressedretriever 126 shown in the form of a pivotally mounted lever normallypressed in engagement With the side of the rack 111 by a spring 127. Theforward; movement of the rocker 123, and thus of the paWl 118 intoengagement with the rack 111 will rock a locking pawl 128 intoengagement with one of the teeth ofthe escapement Wheel 109, so as toprevent the carriage 7 from moving forward under the pull of the springWhile the back spacing key is depressed. e

The pinion 110 is connected to the escapement Wheel 109 by apawl-andratchet mechanism, so that the carriage can move .backwardlywithout rotating the escapement Wheel 109 While the rack 111 is still inen- This enables the striking of successive character keys in the `sameletter'space While the back spacing key is .depressed without feedingthe carriage in a letter feeding direction.

Advantage is taken of the need to return to a previousletter space bymeans of the back spacing key, to actuate the shifter. 94

against the tension of a spring 129, which normally holds lthe clutches62 and 93 in connection with the gears and 91. For

this purpose the back spacing key114 is pro- 'vided with a dependinglink'130, which has at its.lower I end a pin-andfslot, connection 131with one arm of'a rocker 132 pivotally mounted intermediate its ends at133. Theother arm of this .rocker 133 is provided with a finger. 134havingV an inclined cam surface 135 which is adapted to engage a pin 136secured to an arm 137 on a rock shaft 138. `The rock Shaft=138 ex'-tends to a pointwhere itis ,provided with a segment bevel gear 139 Whichmeshes with a correspondingv segment bevel gear .140 on a shaft 141. Theshaft 141 is lprovided with an arm 142V having aslot 143 therein,Whereby it engages lwith a pin 1,44 on the rod Aof the shifter .94. Itwill -thus be seen that when the spacing key .113 is depressed, it willnot only back space the carriage, .but it will also manipulate, throughthe intermediary of the connecting mechanism, the shifter 94 against thetension of the spring 129, so as to manipulate the clutches 62 and 93from engagementl with the gears 60 and 91 into engagement with the gears61 and 92.

In taking up the operation of the device, We will assurnethat an' errorhas been made with thelastkeys'truck, andit is desired to eliminate'the:same from all of the com'- puting headsl which happened to be acting,`Whether they werel adding or subtracting. To do this, it is merelynecessar tor depress the back spacing key 113, where y the pawl 118 willbe rocked forward until comes in' engagement with the teeth of ,thelrack 111 when it'will be swung against the tension of the spring 128 soas to m'ovethe carriage 7 back jone. letter or character space. V

The movement ofthe rocker 123 which carries the pawl 118'Will cause'theconcomitant movement of the'locking paWl 128 into the pathof oneoftheteethof the escapement Wheel109, so that even. if one of thenumeral keys were 'struck while the back spacing key 113, is depressed,the carriage would not be yfed forward in theusual manner. At the sametime that the back spacing key returns the carriage one space, itactuates, through the intermediary of the connecting mechanism, theshifter 94, so as to bring the clutches 62 and 93 from engagement Withthe gears 60 and 91 into engagement With the gears 61 and 92, wherebythese latter gears will4 be vin driving rela. tion Withthe shafts 28 and29. This action will reverseI the direction of vdrive of the gearingconnected ito both the master Wheels and the tens carrying mechanism ofall of the computing heads, Without disturbing their independentcontrol, so that vsuch of said computing heads as were adding, at thenext actua-tiem of a lnumeral key, will subtract, and vice versa. Whilethe back spacing key is still depressed, the same numeral keywhichcommitted the error will be struck, so as to take out the exact amountof error whichvis put Ainto each of the computing heads, that sav. if.this. number-Were previously-- iisd@ t0 are? caler calamities headnt wilb-Sabtracte f and if. .were subtracted, Will bwddad, SQ' esta' eliminatetheervawommitted- It Willbe-seeathat--., .nach tbeloekf ine' iva-w1,128. Still' mies .1u engagement 'with one 0f die .teeth the Wheeh that-Sd.1011s.aslthabacksnaiaa key is depresseathe aarriaeevaillfnotte lie: fQrwavd.. The back s aealakeyis .lienrl ...edi leaving @particuarletterapaiel: iii-euml; umn ia whehth @ma has been mmmitteclat the.pri-ruinanoint- The ermneousaumeiia which has` struck twice inj the sam' e letter space, can thea-M imm. ,the Sheet Olithe Phmaad asthe ringehas beaheldvin @esame letter Space the proper key can bheubastruek,Sable-1t the: proper numeral-Will be imprinted: 011 the work she-eti andProperly .wniputed Such ofthe computing headsV as be active at this.particular instant.

Variations be. resorted to .Within the SCOP@ Qf'tlle invent-kul, andDQr-iiolls O f the improvements may beused withoutotliers,

Having thus .described my. invention, I clam, 1- The combination with,computing head having aseries of computing Wheels and a r master wheel,said computing- Wheels and said master Wheel hayingamovement relative toeach other, whereby said masterl Wheel may wperate suwessrely; with eachof said computing wheels, of means for rotating` said master Wheel, andautomatic means for concomitantly reversing the direction of rotation ofsaid master Wheel 'and changing the relative position -ofsaid computingWheels. and said master Wheel to a' previous relation. 2. Thecombination with acomputing head capable. of being 4in a pluralityofstates as to adding, subtracting and Vremaining neutral, of a carriage;and automatic means for concomtantlycausingaback- Ward movement of saidcarriage. and chanfging thestate of said'computing-headif 3. Thecombina-tion with a computing head capable of being in a plurality 0iStates as to adding, subtracting and remaining' neutral, of a carriage,and automatic means for4 concomitantly back spacingsaid carriage aindAchanging the state of said computing ead.

4. The combination with a computing head capable of existingy under aplurality of' states as to adding', subtracting and remaining neutral,of a typewriter carriage, a key, means or'ierated by 'said key for backlspacing' said carriage, and means operated by said key for changing thestate of said computing head.

5. The combination with a computing head capable of existing under aplurality off Staines@ adding, Saba-radica and remis: manantial, of:@iQ-ariane, alienware O piatcd-lu/ saflker fdicaiislna aiiwveiientqfcarriage a return direction, and 1 elemental@ Said kei far teeeerafllyciinging thestate of vsaid computinghciad. Then combination ivitliaV'co'inpu tilng lie-.d (Parable 'O f existira undere. plural@ einem Oiawrange. and .i1-.key tba-190er edema-ably accinge back-Walid moieeent ofsaid carriage and changingthelsftatedf Sadfaemputinsfliead,aeaibination. with. computing head including e ,intenable masterWheatland tens. Carini-nga mechanism; or. ge,ari-nef-` for driving-SaidmaSter Wheel haiti-Dafa shifting; ,aiec hansm for .Controlling the drivethereof, gearing for' driving said tens carny, ingm'echanism. having aShifting mechanism; for controlling .the drive vthereof, gearingcontrolling bothsets of said gearing, includingreversing mechanism to'oontrolthe direction 'of rotation thereof, a Cim?- riage, and a key forcontrollingconcomitan, -t ly thennovement of saidA carriage and saidreversing mechanism. ,'8 The combination with a computing head includinga rotatable master Wheel and-tel'isacnryingmechanism, of gearing fordriving saidmasteiwheel having shifting mechanism for controlling thedrive there.- of-,gearing for driving said tens carrying mechanismhaving-a shifting mechanism for controlling drive thereof, gearingcontrolling -both sets of said gearing, including individualreversingmechanism for control-Y ling tlie. direction of said master wheelgearing and said tenscarrying gearing, a carriage, and a key forcausingconcomitantly a movement of said carriage and a shift of both ofsaid individual reversing mechanism's.

9. The combination With a plurality of computing heads, each having atenscarrying -mechanism, a reversing mechanism therefor, a carriage,back spacing mecha-1 nism Afor sai-d carriage', and means operatedbysaidback'spacing'mechanism for shifting .said reversirf mechanism.

10. The combination with a plurality of computingV heads, each having amaster Wheel and tens carrying mechanism, of gearing for driving saidmaster wheels, gearing for driving said tens lcarrying mechanism, eachofsaid gearings including means fo'rcontrolling the 4drive of saidWheels and said tens carrying mechanisms, a carriage, back spacingmechanism for back spacing said carriage, and means operatedh by saidbackspacing mechanism fori controlling both said gearings.

11. The combination with a computing head having a master Wheel and tenscarrying' mechanism, of reversible gearing for driving said masterWheel, reversible gearing [for divinfg y'said' tens "carryingymechanism, 'gearing orA driving 'saidfir's't andseoond mentionedgearing, mclding? a pair of cltches"shift'able t0'f"chan'ge the''direction of ."rotation" ofv said first and second-'mentioned "gearing,meansA for' shifting-f said clutches simultaneously; a 4('Larriage,"back spacing. mechanism' for .back spacing said carriage, land meansoperatedby" said back spacing mechanism -for actating'ffsaidclutchf'shiftngfmeans. A' l' f* i-'f'f 5* 12. The combinationwithlapluralityjo'f computing heads', each 'fineludin a' master wheel'and "al: 1tens' carrying mec anisrn', f ofgegringr fori, driving f saidmaster 'Wheels in either direction', :gearing-for driving said tenscarryinglm'echanisrn `in either direction, gearing 'fori i driving 'saidl'first' and second mentioned gearing, including' apair of shiftableclntches'- vfor f determining f ithe 'direction ofdrive=o1| said' firstand sec'ond mentioned gearingsgfa-'shi'fter connected' to iboth ofsaii'i clutches for shifting 'said clutches' simultanei ously, acarri'age',aibackl spacing mechanism for 'shifting saidficarria'gelfinareturn direction, and connections'betvveen" saiddliackspac-r ingmechanism and'said l'shifter-'for manipulatig said 'shifterf Q 'f V1ffiw@ fi- 13; The combination :withT a' plurality' -lo computing heads,of individual controlling mechanism for determining the rotation anddirection of rotation ofi each computing head, afsupplementarycontrolling mechanism independent of-said individual controllingmechanism for determining the-rota` tion roffsaid computing heads, acarriage, back spacing mechanism for back spacing' said carriage,fand-connections between saidback. spacingfmechanism and saidl second'-mentioned controlling mechanism foracT tuating said second-'mentionedcontrollingE mechanism concomitantly with the back spacing of saidcarriage. r; t; i i

:14. The combination with -a 1,pluralityf-or. computing heads, -ofindividual-controlling4 mechanisms .for determining Whether' saidcomputing heads shall' add=,=v subtract 'ori :re-V main-neutral,:controlling mechanism. Einde-.2 pendent of the actuation'of-said'individualr controllin .mechanisms, :for ,Y enabling theOpposite c aracter of Work iof saidgc'omput-f.

in heads to that determinedflby @the indivi ual controlling 'mechanismswhervin an active osition, .a carriage, back spacing mechanism for backlspacing said-.carri'age,fA

and connections between said back-spacingI mechanism i and saidsecond-mentionedc controlling -mechanism `for actuating :said-second-mentioned controllin mechanism concomitantly -with thebacij;spacing of said carria 15. diie combination. with* a `p1`iirnity ofcomputing heads capable of adding, 'sub" tracting and remaining neutral,of individ-` ual controlling mechanisms for determining state, and sucho said-computing 'heads'fasare inftheir subtracting-lstate"toftlieii"addi ing" 'st'atel` While y'said'"jimiividua 1' controlling mechanismsremain in'tlie oppositej'state', a carriage, "back 'spacing-jmechanism'Ifor back spacing s'aid'carriageg'and (connections be'- tweenI saidvbackf `spacingimec'h'anism 'and saidE second-mentioned controllingmech'a nismz *for v'actuating' said second-mentioned controllingfimechz'mism concomitantly Y 'with th'eA back spacing 0fv said carriage.#ff

"luTh'e combination -wvithfa plurality of computing f lieads`capabl eo'f adding,l sub-4l trating fand'jremainingneutral, 'of' indifvidalcontrolling mechanisms for determine ing :the 'statef'of 'saidcomputing" heads, a supplementary "controlling mechanism 'ca'- p'able:of changing-such osaid computing heads asV are in their-adding state'tQ'thei-r subtracting istat-e, and'such'of said computing heads'afs arein t-heinsubtracting state t'tlieir *adding state, While` leaving'sucho'f Said coni'p'\1'tin`g:,rfheadsy 'asare in 'their neutral statefree from interference, a carriage,1back spacing mechanism foriback-'spacing said carriage,-r and' connections between said backspacing-1- mechanism and said 'l second-finentioned controllingmechanism" for actuating said-second mentioned controlling mechanismconcomitantly with the back Spacing of said carriage.

17,"The combination with a carriage, of a back spabingi'rnechanisrn forshifting said carriage in afreturnidirection, a back spacing l'keyliever jfor voperati-ng 'said back spacing meehanism,'a computing head',means for controlling the state .of said computing head,"an arm foroperating-said means, a shaft actuating said arm, a b'evel gear on saidshaft, a bevel gear meshing with said first-mentioned bevel gear, andconnections betweenv said last-mentioned bevel gearIan'd' saidS-fbackspacing key lever.

18. The-'comb'nation With a carriage,- of a back "spacing mechanism "forshifting said carriage in areturn direction, a back spacing'key leverfor operating-said back spacing "mechanism, a'computing head, 'meansfor-'controlling the stateof said computing head,i an arin forfoperating said' means, 1 a shaft actuating said arm, a bevel ear-ontsa-id':shaft, a bevel -gearmeshing vvlth said first-mentioned bevelgear, a shaft for ro-z tating Said last-mentioned bevel gear,4 an arm onsaid 'last-mentionedsshaft, a rocker: for actuating said last-mentioned'arm, and a link connecting said rocker with said back spacing key lever.Y

19. The combination with a carriage, -of back spacing imechanism forsaid carriage, a key lever lfior actuating said back spacingmechanism, acomputing head lhavinga master Wheel, tens carrying mechanism, gearingfor driving both said master Wheel and said tens carrying mecha nism,individual clutches for reversing said gearings, a shifter formanipulating said clutches, and connections between said Shifter andsaid back spacing key lever, whereby said clutches may be shiftedconcomitantly With the actuation of saidbackspacing mechanism.'

20. The combination ivith'a. ca.r1'.iage,of backspacing mechanism for.said carriage,- a key for controlling said backspacinglmechanism, one ormore computing lieads,:state controlling mechanism for determining. thestate of said computing heads,A and means for temporarily changingrthestate of all-of said computing heads which are active to justthe'opposite state While' said back spacing key is depressed to back4space said carriage. y

9,1. The combination with a carriagc,-Of a plurality of computing headshaving traveling elements, a. key7 and `connections between said key andboth said carriage anidwsalid computing heads, whereby an actuationfofsaid key will concomitantly bring said carriage and said travelingelementS-'backto a previous letter space and also change the state of'all of said computing beads which are active at the instant ofactuationo-f said key. l

22. The combination With a computing head having a series of computingWheels, of a master Wheel movable successively iin'to coperation withthe computing Wheels of said computing head, and an error key forconcomitantly bringing saidV master Wheel back int-o engagementl With aprevious computing wheel, and changing the direction of rotation of saidmaster wheel to just the opposite direction to correct an error'. i

23. The combination with a computing head capable of existing in: aplurality 'of' states as to adding, subtracting and remain-- ingneutral, of a traveling carriage, and means for concomitantly movingsaid carriage backwardly .and changing the state of said computing headat any point of the travel of said carriage for a given adjustment ofsaid head.

24. The combination with a computing head capable of existing in aplurality of states as to adding, subtracting and remaining neutral7 ofa traveling carriage, and means connected to both said carriage and saidcomputing head for concomitantly causing a backward movement of saidcarriage and a change in state of said computing head.

25. The combination with a computing head having a series of computingWheels and a master wheel, said computing Wheels and said master wheelhaving a movement relative to each other whereby said mastervvhee'lllnay cooperate s'erz'at'im witheach -of saidcomputing Wheels, ofmeans 'for' rotating said master Wheel',V andzmeansei'ectve at anyrelative 'position of y'said'fmaster Wheel andsaid computing- Wheels "orwhen said master wheelispositionedv relatively to said computing -wheelsfor concomtantly reversing.' thef direction ofrotationof said masterWheel andbringing. about a previous relative position. of? saidcomputing wheels andi -saiu master Wheel to correct anferror. .1.' f,

26. The vca'nnbination with'a computing unit having a seriesotcomputin'g .-Wheels5 and a master wheel, said eomputing'wh-eels and.lsaid master Wheel` having movement relative'to eachother Vsofas toenable-said master -Wheelto register suecessively'with each of .said'computing Nvflieels54 of ldriving inea-ns for rotating said master.wheelgand a. si nsgle4 means. for` concomitantly.- effectinga relativebackward- -moivement4 between the master Wheel/and thef computing Wheelswithin the range of the conrputimgfilniti and changing the .character-of'rotaticn .of. s the masterA Wh'eeil.- ,i

27. Theicombination with a. seriesof-:compntingyvheels, 4of amasterwheel for driving said: :computing Wheels i serifm, -a reversibledrivefforlsaidzfmaster Wheel,- and :a single means for. bringing aboutthe registration `of said masterw'liee'lfwith a` computingwheel withwhich it was previously in register vso as to' effect a correction. andreversing `thedirlection ofy rotation4 of .said master. wheel fromthiatwhicl'rV it had when' previously in register with such-computingwheel:

Q8.- The combination With a Series of computing Wheels, of a masterWheel' for driving said computing Wheels serzatim, a. reversible drivefor said masterawheel, a space key connected to ei'ect a lrelativebackward ifnovement between saidi .ma sterf=wheel and said computingWheels, .and connections from said space key to saidl reversible driveenabiing' said space key to change the character of rotation of saidmaster wheel.

29. The combination with a plurality of computing Wheels, of actuatingmechanism for driving said computing Wheels, a series of numeral keysfor controlling the extent of movement of said actuating mechanism tocorrespond With the value of the numeral keys actuated, means foreffecting denominational selections so that the successive actuations ofnumeral keys corresponding to successive denominations or digit columnswill enable the operation by said actu ating mechanism of thecorresponding computing Wheels, and correction mechanism actingautomatically to both bring said actuating mechanism in play withrespect to a given computing wheel previously incorrectly rotated, andreverse the direction of actuation of said actuating mechanism to takeout the number incorrectly run on such computing wheel.

3 0. The combination with a computing head, including a series ofcomputing wheels and a master Wheel for driving said computing Wheelsseri'atz'm, of state-changing means orvarying' the rotation of saidmaster wheel, back-spacing mechanism for -eiecting a backward relativestep movement lbetween said computing Wheels and .said master wheel,yand a single element having a connection to said state-changing meansand another connection to said 'back-spacing mechanism whereby it mayoperate both said state-changing means and said back-spacing mechanismat the same time.

31. The combination with a computing mechanism, including a seriesvofcomputing Wheels,of lv carriage traveling to eectdenominational'selections With respect to said computing Wheels,reversible mechanism independent of the movement of said carriage foreffecting a change of 'state in said computing mechanism at'anyletter'space interval in lthe travel of said carriage and at will,spacing means for causing the movement of said carriage, and a singlemember for--actuating both said spacing means and said reversible:mechanism concomitantly.

32. The combinationl with fa='computing. unit capable of existing undera' plurality of states as to adding, subtracting, and neutral, of acarriage traveling interzonally to determine different computing zonesof said computing unit, andtraveling intrazonally'to determinedenominational selections in zones for said computing unit, and a singlekey for both changing the state of said computing unit and effecting anintrazonal movement of said carriage and thus a denominational selection or' said computing unit.

33. The combination with a computing unit including a series ofcomputing wheels and a master wheel, saidcomputing :Wheels Uoplel o(this patent may be obtained for and said master wheel having a relativemovement so lthatsaid master Wheel may drive said computing Wheelssuccessively when said master wheel is. Within the range of saidcomputing'wheels and thus Within a computing zone, ofintrazonally-acting means for concomitantly reversing the direction ofrotation of said master Wheel and Changing the relative position between.said computing Wheels and said master wheel, so that Saidmaster WheelWill return from -register With one lcomputing wheel to register withthe computing Wheel with which it was previously in register.

34.- The combination with a computing unit lcapable of existing under aplurality of states as t0-adding,subtracting and neutral, of a travelincarriage controlling denominational selections of said computing unit,said carriage traveling also to determine computing zones and havingstep-by-Step movements when in the range of a computing zone, andautomatic means acting intrazonally in one movement to concomitantlybacl space said carriage and change the stateof said computing, unit. Y

35; The combination with a computing unit capable of existing under aplurality of states as to adding, subtracting and neutral, oi-'acarriage-traveling interzonallv to determine several computing zones forsaid computing unit, and traveling step by step intrazonally to deteminedenominational selections in zones for saidcomputing unit, and a commonmeans for controlling both the state of said computing unit as to thecharacter of computation and certain intrazonal traveling movements vofsaid carriage.

WALTER WRIGHT.

Witnesses:

PAUL ZIRON, LORENZ L. PRrrzL.

ve cents each, by addressing the Commissioner of Patents, Washington, D.C.

